Flashers and circuits therefor



United States Patent ,FLASHERS Anncmcmtrs THEREFOR Jesse B. vHollins, Brooklyn, Ni)! assignor toLSignaI-Stat Corporation, Brooklyn, N.Y., a corporation'of New ,;This invention relates to intermittently energized .or tflashing signal and indicating circuits and, :more particularly, to novel circuits of {this typeiincluding a noyel \flasher comprising a-tbermomotive element -.,eont rolling current flow thro gh Parallel "load circui in accordance with the invention, a flasher is provided in which the operating elements. are .enclosed .a sealed ienuelope which may %be evacuated .or else .filledwjth an :inerttgas. This envelopeis sealed to at these having three terminals, :the usual :s'ide terminal and :two endwterrninal The base may be either -a bayonet :typc,,:s.u ch as usedjn automotivewehicle lamps, -,or azscrew .type. The :envelope contains :a high resistance filament supported lbetweena pair of conductors, :one connected to ,a side terminal of 'the base and ithe other connected :ttonn end terminal of the base. .A thermomotivetconductor, such as a bimetallic strip, is connected :to ?t'h6\!tl16l.baS8 terminal and is normally engaged with tthe filament {SGH- ductor connectedto a -.base:termina;1.. I

In -the circuits utilizing @the flasher, ithe side terminal is connected "to ground, the filament base end terminal is connected to a load such as grounded signal lamps, and the thermomotive element terminal :is connected :to a grounded source of potential. Switch means are 'provided in the circuit leading to such source and in one of the other circuits, the switch means comprising a double pole switch. I

When the switch means is closed, current fiows from and conductors 1 8 and 27.

the source through the. thermomotive element ,and then the filament .base end terminal conductor. The .fllarnent and load circuits are thus opened, and the filamentcools. .Af -ter sufiicient cooling, the thermomot'ive element. re -en- ,ment which, ,upon sufficient heating, deflects to disengage gages the filament conductor ,to reiclosegthe filament and load circuits, and the cycle repeats.

For an understanding of the invention principles, reference is made to the following description of typical embodiments thereof as illustrated in the accompanying drawings. In the drawings:

FIGS. 1 and 2 are schematic wiring diagrams of an automotive vehicle turn signal system embodying the invention, respectively illustrating the circuit closed and circuit open conditions; and

FIGS. 3 and 4 are corresponding schematic wiring diagrams of an automotive vehicle turn signal system embodying a preferred circuit arrangement of the invention.

The circuits shown in each of the four figures include a flasher 10 comprising a sealed envelope 11 sealed to a base 12. Envelope 11 may be evacuated or may be filled with an inert gas. Base 10 includes the usual side terminal 13 and central terminals 14 and 16. Envelope 11 contains a high resistance filament 15 mounted on a conductor 17, connected to contact 13, and a conductor Patented Aug. 15, 1961 .typegengaged in .a bayonet ,type socket 25 including n conductive tmetal-side wall .22 engaging (base r12 -6terminal 1.3,); and :spti g [biased contacts ,24, 26respectiyely engagling hasetend terminals ,14 and- Gontaots :24, 6Z6. .are insulated. .trom base 25 in ,themanner customary with automotive yehiclqtlamp :soc'ltets, .and,are iconnected tto conductors 27, 28, respectively; Base sidewall. 22 connected :to a inductor- 23. I

, iIntthe turn signal circuittof FIGSLJ and 2., conductors 23 .and .27 are connected-to, the mova le arm 13.2 of a double pole, double throw turn signal :switch ;3 0,;-and :conductor 28 istconnected io =theL-live {terminal 3,6,.0f..,a grounded battery 35 representative of :the electriezpotentialsourne of an automotive vehicle.

sswitchzarm .31.;is adaptedto engage either .of a pairlof :contacts 33,.33which, in FIGS. 1;.and.2,;are grounded. Switch arm 325s arranged to engage a contact 34Ltor '21 contact 34R. iCOIllHCt- 54L is connected to grounded left turn signal .:lamps LF .and LR, and contact 34R :is connected :to right J-turn ssignal =lamps RF and 'RR. In :the turn signal :arrangement of FIGS. 3 .anda l, contductor 23 -?is connected directly to ground and conductors 28 and 2%7 are connected to switch arms 31 and '82,..re- "spectively. Contaots 33 are connected to live terminal '36 of battery 35 ahtl contacts 34L :and 34R are connected in the same manner a's in FIGS- 1 and'2. I

'-In the *system of FIGS. 1 and '2, when switch 30 is toperated to signal a right turn, for example, an arm 3E1 engages a-zgrounded-contact 33 and arm 32 engages contact 34R. Gurrent flows from battery 35 through iterminal 36, conductor 28,-contacts '26 and 16, element '20, The current then fiows through 'a pair of parallel circuits. One circuit comprises conductor 18, filament 15, conductor 17;, conduc- :tor '23, arm 31, contacts 33 and ground. "The other cireu'it comprisesconductor :18, contacts 14 and 24, conductor 27,=-arm 32, contact 34R, and lamps RF andRR in "parallel to ground. As filament 'heats 'the' interior of envelope "1 1', 'e'lement ill-heats and *deflectsaway "from conductor 18 as "shown-in FIG. Current ceases to new "in both the parallel load circuits, 'and lamps "RF. and RR and tharnent15 are extinguished. As filamentSIS' cools, element"20 cools and :reengages conductor '18. The cycle he e 7 7 The preferred arrangement of FIGS. '3 and 4' operates in' an equivalent manner. In this arrangement, base '25 is always grounded and battery 35 is connected to element 20 only when switch 30 is moved from neutral to either operated position. An arrangement of this type is preferable to that of FIGS. 1 and 2 for safety reasons due to the unbroken ground circuit of socket 25.

In both embodiments, known pilot lamp arrangements may be used, as well as the pilot lamp operators of my copending application Serial No. 716,649, filed February 21, 1958, issued as Patent No. 2,942,236 on June 21, 1960, and my copending application Serial No. 717,164, filed February 24, 1958, and issued December 29, 1959, as Patent No. 2,919,424.

While specific embodiments of the invention have been shown and described in detail to illustrate the application of the invention principles, it will be understood that the invention may be embodied otherwise without departing from such principles.

' What is claimed is:

1. A thermostatic circuit interrupter or flasher comprising, in combination, a sealed envelope; a base sealed to said envelope and having three terminals; a high resistance filament in said envelope; a pair of conductors projecting substantially from said base into said envelope and each having one end connected to a pair of base terbetween said conductors and connected to the third terminal, thefree end of said element being normally engaged with an intermediateportion of one filament conductor within said envelope; said element, when heated due to heating of the interior of the envelope by said filament when current flows through the latter, disengaging said one filament conductor.

2. A thermostatic circuit interrupter or flasher comprising, in combination, a sealed envelope; a base sealed to said envelope and having three terminals; a high resistance-filament in said envelope; a pair of conductors projecting substantially from said base into said envelope and each having one end connected to a pair of base terminals, the opposite ends of said conductors being connected to opposite ends of said filament; and a thermomosaid disengagement, said filament will cool and said ele-" ment will re-engage said filament conductor.

3. An intermittently energized electrical system comprising, in combination, a thermostatic flasher including a sealed envelope, a base sealed to said envelope and having three terminals, a high resistance filament in said envelope, a pair of conductors projecting substantially from said base into said envelope and each having one .end connected to a pair of base terminals, the opposite .ends of said conductors being connected to opposite ends h .of said filament and a thermomotive element extending s from said base into said envelope between said conductors and connected to the third terminal, the free end of said element being normally engaged with an intermediate ,portion of one filament conductor within said envelope,

said element, when heated due to heating of the interior .of the envelope by said filament when current flows through the latter, disengaging said one filament conductor; a source of potential; a first load circuit connected to one of said pair of terminals; a second load circuit connected to the other of said pair of terminals; a supply circuit connected to said source and to said third terminal; and normally open conjointly operable switch means in two of said circuits controlling the simultaneous connection of said two circuits to their respective terminals.

4. An intermittently energized electrical system comprising, in combination, a thermostatic flasher including a sealed envelope, a base sealed to said envelope and having three terminals, a high resistance filament in said en'- velope, a pair of conductors projecting substantially from said base intosaid envelope and each having one end connected to a pair of base terminals, the opposite ends of said conductors being connected to opposite ends of 'said filament and a thermomotive element extending from said base into said envelope between said conductors and connected to the third terminal, the free end of said element being normally engaged with an intermediate portion of one filament conductor within said envelope, said element, when heated due to heating of the interior of the envelope by said filament when current flows through the latter, disengaging said one filament conductor; a source of potential; a first load circuit connected to one of said pair of terminals; a second load circuit connected to the other of said pair of terminals; a supply circuit connected to said source and to said third terminal; and normally open conjointly operable switch means in said supply circuit and one load circuit controlling the simultaneous connection of said supply circuit and said one load circuit to their respective terminals.

v5. A system as claimed in claim 3 in which one of said load circuits is, directly grounded and the other load circuit comprises a grounded lamp load.

, 6. A system as claimed in claim 3 in which said switch means comprises a double pole selector switch having a neutral position and a pair of operated positions; one pole of'said selector switch, in either operated position, connecting one circuit to its terminal; the other pole of said selector switch being connected to the respective terminal of its circuit and being selectively engageable with either of a pair of contacts; and sets of turn signal lamp means, each being connected to one of said contacts.

References Cited in the file of this patent UNITED STATES PATENTS 2,030,664 Theilacker Feb. 11, 1936 2,321,803 Falge June 15, 1943 2,477,408 Gross July 26, 1949 2,669,704 Hollins Feb. 16, 1954 2,689,283 Pulvari Sept. 14, 1954 2,840,796 Hollins June 24, 1958 2,911,620 Scherenberg Nov. 3, 1959 

